• Title/Summary/Keyword: APPROACH SHOOT

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Approximate Dynamic Programming Based Interceptor Fire Control and Effectiveness Analysis for M-To-M Engagement (근사적 동적계획을 활용한 요격통제 및 동시교전 효과분석)

  • Lee, Changseok;Kim, Ju-Hyun;Choi, Bong Wan;Kim, Kyeongtaek
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.50 no.4
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    • pp.287-295
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    • 2022
  • As low altitude long-range artillery threat has been strengthened, the development of anti-artillery interception system to protect assets against its attacks will be kicked off. We view the defense of long-range artillery attacks as a typical dynamic weapon target assignment (DWTA) problem. DWTA is a sequential decision process in which decision making under future uncertain attacks affects the subsequent decision processes and its results. These are typical characteristics of Markov decision process (MDP) model. We formulate the problem as a MDP model to examine the assignment policy for the defender. The proximity of the capital of South Korea to North Korea border limits the computation time for its solution to a few second. Within the allowed time interval, it is impossible to compute the exact optimal solution. We apply approximate dynamic programming (ADP) approach to check if ADP approach solve the MDP model within processing time limit. We employ Shoot-Shoot-Look policy as a baseline strategy and compare it with ADP approach for three scenarios. Simulation results show that ADP approach provide better solution than the baseline strategy.

Four Novel PWM Shoot-Through Control Methods for Impedance Source DC-DC Converters

  • Vinnikov, Dmitri;Roasto, Indrek;Liivik, Liisa;Blinov, Andrei
    • Journal of Power Electronics
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    • v.15 no.2
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    • pp.299-308
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    • 2015
  • This study proposes four novel pulse width modulation (PWM) shoot-through control methods for impedance source (IS) galvanically isolated DC-DC converters. These methods are derived from a PWM control method with shifted shoot-through introduced by the authors in 2012. In contrast to the baseline solution, where the shoot-through states are generated by the simultaneous conduction of all transistors in the inverter bridge, our new approach is based on the shoot-through generation by one inverter leg. The idea is to increase the number of soft-switched transients and, therefore, decrease the dynamic losses of the front-end inverter. All the proposed approaches are experimentally verified through an insulated-gate bipolar transistor-based IS DC-DC converter. Conclusions are drawn in accordance with the results of the switching loss analysis.

Shoot Induction and Genetic Stability of in vitro Cultured Pea

  • Kantayos, Vipada;Bae, Chang-Hyu
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2019.10a
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    • pp.30-30
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    • 2019
  • Pea (Pisum sativum) is one of important legume crops in the world. It is commonly used as a protein source for animal and human diet, and also used as a natural nitrogen source which is produced by a symbiotic bacterium in their root nodule and helpful for terrestrial ecosystem. The successful in vitro manipulation is depended on three main factors including physiology of plant donor, in vitro manipulation approach, and stress physiology during plant cultivation. Moreover, genotype is an important for plant manipulation; different genotype gives the different response to regeneration efficiency. An efficient condition of shoot induction for pea (Pisum sativum cv. 'Sparkle') was developed by using optimum explant, plant growth regulator concentrations, and pretreatment of BA onto explant. The average shoot number per explant showed the highest on two kinds of shoot induction media (MSB5 media containing 2 mg/L BA and a combination of 2 mg/L BA and 1 mg/L TDZ) with cotyledonary node explants culture. Moreover, the pretreatment of explant in 200 mg/L BA solution was found to be more effective in shoot induction than that of non-pretreatment. The analysis of genetic stability of regenerants by using 13 ISSR markers presented that in vitro regenerated plants showed polymorphism with 8.3% compared with their mother plants.

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A Gate Drive IC for Power Modules with Shoot-through Immunity (상단락 방지용 모듈을 구동하기 위한 게이트 구동 IC)

  • Seo, Dae-Won;Kim, Jun-Sik;Park, Shi-Hong
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.22 no.7
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    • pp.580-583
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    • 2009
  • This paper introduces a gate drive IC for power modules with shoot-through immunity. A new approach uses a bootstrap diode as a high-side voltage bias and a level shift function at the same time. Therefore, the gate drive circuit becomes a simple and low-cost without conventional level shift functions such as HVIC(High-Voltage IC), optocoupler and transformer. The proposed gate drive IC is designed and fabricated using the Dongbu-Hitek's 0.35um BD350BA process. It has been tested and verified with IGBT modules.

A Gate Drive IC for Power Modules with Shoot-Through Immunity (상단락 방지용 모듈을 구동하기 위한 게이트 구동 IC)

  • Seo, Dae-Won;Kim, Jun-Sik;Park, Shi-Hong
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2009.04b
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    • pp.81-82
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    • 2009
  • This paper introduces a gate drive IC for power modules with shoot-through immunity. A new approach uses a bootstrap diode as a high-side voltage bias and a level shift function at the same time. Therefore, the gate drive circuit becomes a simple and low-cost without conventional level shift functions such as HVIC(High-Voltage IC), optocoupler and transformer. The proposed gate drive IC is designed and fabricated using the Dongbu-Hitek's 0.35um BD350BA process. It has been tested and verified with IGBT modules.

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Kinematic Factors Influencing on the Precision of Short Approach Shoots in Golf (골프의 짧은 어프로치 동작 시 타구의 정확성에 영향을 미치는 운동학적 변인 분석)

  • Kim, Ho-Mook;Woo, Sang-Yeon;Jung, Seung-Eun
    • Korean Journal of Applied Biomechanics
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    • v.17 no.2
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    • pp.227-237
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    • 2007
  • The purpose of this study was to examine the effect of precision that kinematics had when short approach shots were taken. In this study, the subjects chosen were 5 skilled and 5 unskilled subjects, who were allowed to shoot 10 rounds of shots at target distances of 1m, 2m, 4m, and 8m. Three dimensional analysis was used as methods to obtain kinematics of each shots. In order to verify the statistical significance of the kinematic factors followed by the results of different skills and target distances, we used the two-way repeated ANOVA. The study was experimented within the level of p<.05. The results obtained were as follows: 1) the difference of shots of the forward and backward variations were larger than those of the left and right variations, the unskilled subjects' shot distances greatly got larger than that of the skilled subjects as the distance of the target increased, 2) not being affected by the target distance variations, the skilled subjects' rate of down-swing was shorter than the back-swing on short approach shots, 3) the skilled subjects' center of body weight tended to move more naturally towards the target when doing the down-swing to finish than that of the unskilled subjects on short approach shots, 4) the skilled subjects' right hand angle of cocking were narrower and tended to be kept much more consistent than that of the unskilled subjects on short approach shots, 5) the unskilled subjects when doing their back-swings, their right hips swayed towards the back, their trunk-flexion angles were shown to be lower than that of the skilled subjects on short approach shots, 6) the skilled subjects`body weight tended to move more naturally towards the left foot when doing the down-swing to finish than that of the unskilled subjects on short approach shots.

Highly efficient production of transgenic Scoparia dulcis L. mediated by Agrobacterium tumefaciens: plant regeneration via shoot organogenesis

  • Aileni, Mahender;Abbagani, Sadanandam;Zhang, Peng
    • Plant Biotechnology Reports
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    • v.5 no.2
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    • pp.147-156
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    • 2011
  • Efficient Agrobacterium-mediated genetic transformation of Scoparia dulcis L. was developed using Agrobacterium tumefaciens strain LBA4404 harboring the binary vector pCAMBIA1301 with ${\beta}$-glucuronidase (GUS) (uidA) and hygromycin phosphotransferase (hpt) genes. Two-day precultured leaf segments of in vitro shoot culture were found to be suitable for cocultivation with the Agrobacterium strain, and acetosyringone was able to promote the transformation process. After selection on shoot organogenesis medium with appropriate concentrations of hygromycin and carbenicillin, adventitious shoots were developed on elongation medium by twice subculturing under the same selection scheme. The elongated hygromycin-resistant shoots were subsequently rooted on the MS medium supplemented with $1mg\;l^{-1}$ indole-3-butyric acid and $15mg\;l^{-1}$ hygromycin. Successful transformation was confirmed by PCR analysis using uidA- and hpt-specific primers and monitored by histochemical assay for ${\beta}$-GUS activity during shoot organogenesis. Integration of hpt gene into the genome of transgenic plants was also verified by Southern blot analysis. High transformation efficiency at a rate of 54.6% with an average of $3.9{\pm}0.39$ transgenic plantlets per explant was achieved in the present transformation system. It took only 2-3 months from seed germination to positive transformants transplanted to soil. Therefore, an efficient and fast genetic transformation system was developed for S. dulcis using an Agrobacterium-mediated approach and plant regeneration via shoot organogenesis, which provides a useful platform for future genetic engineering studies in this medicinally important plant.

Somatic embryogenesis from the axillary meristems of peanut (Arachis hypogaea L.)

  • Singh, Shweta;Hazra, Sulekha
    • Plant Biotechnology Reports
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    • v.3 no.4
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    • pp.333-340
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    • 2009
  • Developmental anomalies in the plumule meristem of peanut (Arachis hypogaea L.) somatic embryos resulted in poor shoot differentiation and reduced plant recovery. Existing meristems with caulogenic potential have never been tested for embryogenesis in peanut. The present experiment was designed to test the mature zygotic embryo axis derived plumule with three meristems for somatic embryogenesis. Embryogenic masses and embryos developed from the caulogenic meristems in the axils. Exposure of 2 weeks in primary medium with $90.5{\mu}M$ 2,4-D suppressed the shoot tip differentiation temporarily which then regained the ability to form the shoot on withdrawal of 2,4-D. Exposure of 4 weeks in primary medium with $90.5{\mu}M$ 2,4-D suppressed the shoot tip differentiation irreversibly. No shoot formation was noted from the tips in any of the cultures which were in secondary medium with $13.6{\mu}M$ 2,4-D. Development of somatic embryos directly from axillary meristems was confirmed histologically. Conversion frequency of these embryos was 11%. Thus, in this report, we describe a method to obtain somatic embryos from the determined organogenic buds of the axillary meristem, by culturing the nodal explant vertically on embryo induction medium. It also displays the possibility of obtaining both embryogenic and organogenic potential in two parts of the same explant simultaneously. The possibility of extending this approach for genetic transformation in in vivo system through direct DNA delivery or Agrobacterium injection in meristems can also be explored. Using Agrobacterium rhizogenes, we have demonstrated the possibility of gene transfer in the axillary meristems of seed-derived plumule explant.

Simultaneous Determination of Statins in Human Urine by Dilute-and-Shoot-Liquid Chromatography-Mass Spectrometry

  • Jang, Haejong;Mai, Xuan-Lan;Lee, Gunhee;Ahn, Jae Hyoung;Rhee, Jongsook;Truong, Quoc-Ky;Vinh, Dinh;Hong, Jongki;Kim, Kyeong Ho
    • Mass Spectrometry Letters
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    • v.9 no.4
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    • pp.95-99
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    • 2018
  • An innovative, simple, and rapid assay method based on liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) was developed and validated for the simultaneous determination of eight statin drugs in human urine. A simple sample clean-up procedure using the "dilute and shoot" (DAS) approach enabled a fast and reliable analysis. The influence of the dilution factor was investigated to ensure detectability and reduce the matrix effect. Chromatographic separation was performed on a Phenomenex Kinetex C18 column ($50{\times}3.0mm$ i.d., $2.6{\mu}m$) using an elution gradient of mobile phase A composed of 0.1% acetic acid, and mobile phase B composed of acetonitrile, at a flow rate of 0.35 mL/min. Quantitation was performed on a triple quadrupole mass spectrometer operated in multiple reaction monitoring (MRM) mode using electrospray ionization in positive ion mode. The total chromatographic run time was 15 min. The method was validated for selectivity, sensitivity, recovery, linearity, accuracy, precision, and stability. The present method was successfully applied to the analysis of Rosuvastatin in urine samples after oral administration to healthy human subjects.

Physiological and Proteomics Analysis to Potassium Starvation in Rice

  • Kim, Sang-Gon;Wang, Yiming;Lee, Chang-Hoon;Chi, Yong-Hun;Kim, Keun-Ki;Choi, In-Soo;Kim, Yong-Chul;Kang, Kyu-Young;Kim, Sun-Tae
    • Korean Journal of Environmental Agriculture
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    • v.30 no.4
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    • pp.395-401
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    • 2011
  • BACKGROUND: Potassium (K) is one of the macronutrients which are essential for plant growth and development. Its deficiency in paddy soils is becoming one of the limiting factors for increasing rice yield in Asia. METHODS AND RESULTS: To investigate physiological symptoms under K-starvation (NP) compared with complete media (NPK) condition, we measured shoot/root length, weight, nutrients, and patterns of protein expression. The shoot growth was significantly reduced, but root growth was not affected by K-starvation. However, biomasses were decreased in both shoot and root. Uptake of K was reduced up to 85%, while total concentrations of P, Ca, Mg, Na were increased in root and shoot. To better understand the starved K mechanism of rice, comparative proteome analysis for proteins isolated from rice leaves was conducted using 2-DGE. Five spots of differentially expressed proteins were analyzed by MALDI-TOF MS. Analysis of these K-starvation response proteins suggested that they were involved in metabolism and defense. CONCLUSION(s): Physiological and 2-DGE based proteomics approach used in our study results in observation of morphology or nutrients change and identification of K-starvation responsive proteins in rice root. These results have important roles in maintaining nutrient homeostasis and would also be useful for further characterization of protein function in plant K nutrition.